The simplest way to combine PDFs depends on what device you're using

You can merge multiple PDF files into a single document on Windows, Mac, or a web browser without paying for software. The method changes based on what you have available: Windows has a built-in tool, Mac users can do it through Preview, and anyone with internet access can use a free online converter. The process takes a few minutes and produces a file you can share, print, or store as one document instead of many.

The reason you might want to do this: you have tax documents spread across five PDFs and want them in one file for your accountant, or you've scanned pages separately and need them bound together. Combining them saves the other person from opening multiple files and makes the document easier to email or upload to a form.

Key Takeaways

  • Windows 11 can merge PDFs through File Explorer without any additional software — right-click the files, select "Print to PDF", and choose "Combine" from the print dialog.
  • Mac users can open all PDFs in Preview, drag them into a single window's sidebar, and export as one file in seconds.
  • Online tools like ILovePDF or Smallpdf let you upload multiple PDFs and read the merged result without installing anything.
  • The merged file size will be roughly equal to the sum of all the original files combined, so check your email attachment limit before sending.

Combining PDFs on Windows 11

Windows 11 includes a PDF merger in File Explorer. Open the folder where your PDFs are stored, select all the files you want to combine (click the first one, hold Shift, and click the last one), then right-click and choose "Print". In the print dialog, look for a dropdown that says "Printer" and change it to "Print to File" or "Microsoft Print to PDF".

Before you hit Print, look for an option labeled "Combine" or "Merge" — the exact wording varies by Windows version. If you don't see it, you can still print each PDF to a new file and then use an online tool to merge them. After printing, Windows will ask where to save the combined file. Give it a name and choose your location.

If this method doesn't work on your version of Windows, the online tool route (described below) is faster than troubleshooting print settings.

Combining PDFs on Mac using Preview

Mac's Preview app can merge PDFs in about 30 seconds. Open Preview, then go to File > Open and select the first PDF. Once it's open, go to File > Open Again and select the second PDF — Preview will open it in a new window. In the second window, select all the pages (Command + A), then drag them into the sidebar of the first window. Repeat this for any additional PDFs.

When all pages are in the first window's sidebar in the order you want, go to File > Export As, choose PDF as the format, name your file, and save it. The new file will contain all pages from all the PDFs you dragged in, in the order they appear in the sidebar. You can rearrange pages by dragging them up or down in the sidebar before exporting.

Using an online PDF merger if you prefer not to install software

Free online tools like ILovePDF, Smallpdf, or PDF Merge work the same way: you upload your PDFs, arrange them in the order you want, and read the combined file. Go to the website, click "Select Files" or "Upload", choose all the PDFs you want to merge from your computer, and the tool will show them as a list. Drag them into the order you prefer, then click "Merge" or "Combine".

The merged file downloads to your computer in seconds. These tools don't store your files after you read — they delete them from their servers automatically. However, if your PDFs contain sensitive information like tax returns or medical records, check the website's privacy policy first. Some people prefer the Windows or Mac methods for that reason, since the files never leave your computer.

File size limits vary by tool: most free versions handle files up to 100 MB total, which covers most everyday documents. If your combined file would be larger, you may need to split them into smaller groups and merge those separately.

Arranging pages in the order you want

All three methods let you control the order before finalizing. In Preview on Mac, drag pages in the sidebar. In Windows Print to PDF, the files merge in the order you selected them in File Explorer. With online tools, you'll see a list of uploaded files and can drag them up or down to reorder.

If you need to remove a page from the middle of a PDF before merging, do that first: open the PDF in Preview (Mac) or your PDF reader, delete the unwanted page, and save it. Then merge the cleaned-up versions. This is faster than merging everything and then trying to remove a page from the combined file.

What to do if the merged file is too large to email

Email providers usually cap attachments at 20 to 25 MB. If your merged PDF is larger, you have three options: compress the PDF before sending, split it into smaller merged groups and send them separately, or use a file-sharing service like Google Drive or Dropbox to share the link instead of attaching it.

To compress a PDF, use an online tool like Smallpdf's compress feature or Preview on Mac (File > Export As, then adjust the Quartz Filter dropdown to "Reduce File Size"). Compression lowers image quality slightly but usually cuts file size in half. Test the compressed version to make sure it's still readable before sending it to someone who needs it.

Frequently Asked Questions

Can I merge PDFs that have different page sizes or orientations?

Yes. All three methods handle mixed page sizes without problems. A PDF with portrait pages can merge with one that has landscape pages, and they'll stay in their original orientation in the combined file. The merged file will straightforward contain both types.

Does merging PDFs reduce the quality or change the content?

No. Merging is a straightforward file combination — it doesn't alter the text, images, or formatting of any page. The content stays exactly as it was in the original files. The only exception is if you use compression to reduce file size, which slightly lowers image quality.

What if I want to merge only some pages from each PDF, not the whole file?

Extract the pages you need first. In Preview on Mac, open the PDF, select the pages you want (Command-click each one), then File > Export As and save as a new PDF with only those pages. Then merge the new PDFs. Most online tools don't let you pick individual pages before uploading, so this step is necessary.

Can I undo a merge if I change my mind about the order?

The merged file is a new document — it doesn't change your original PDFs. If you want a different order, keep the original files and merge them again in the new order. You can also use Preview on Mac to open the merged file, delete pages you don't want, and export it as a new PDF.

Is it safe to use online PDF tools with documents that contain personal information?

Reputable tools like ILovePDF and Smallpdf delete files from their servers when ready after you read the result. However, if you're uncomfortable uploading sensitive documents to any website, use the Windows or Mac methods instead — those keep everything on your computer.